1. Field of the Invention
The subject method and system for fabricating elastomeric articles is generally directed to the fabrication of articles from scrap or waste rubber products, scrap or waste plastic products, and selected additive compositions. More specifically, the subject method and system is directed to the fabrication of a substantially finished product contemporaneously with the material compounding process necessary to prepare the scrap or waste rubber products for use in such final product fabrication. The subject method and system provides for the pre-processing of rubber-containing feedstock to form a viscous elastomer compound followed by a substantially contemporaneous roll molding of the viscous elastomer compound as it is formed.
With the need to conserve natural resources and reduce the generation of waste products becoming evermore apparent, the need to productively utilize scrap or recyclable waste materials has become equally apparent. The need for such productive utilization of scrap or waste materials is particularly great in the case of materials containing rubber or the like for which safe and effective disposal means are not presently available. Consequently, much focus has been placed on fabricating useful articles from scrapped or recycled rubber-containing materials.
One type of such rubber-containing material is commonly referred to as `crumb rubber` which results from the comminution of scrap or recycled vulcanized rubber tire materials. As the typical end product of tire recycling operations, crumb rubber is widely available commercially for use as feedstock in various fabrication/production processes.
The typical approach in forming elastomeric articles is to introduce into an injection molding process a thermoplastic resin which cures within a mold of preselected contour and configuration. The thermoplastic resin is invariably the product of its own manufacturing process and, in most applications, is commercially procured in compounded pellet form. Significant time and expense is unnecessarily consumed by employing separate manufacturing processes for compounding a feedstock into a molding process-ready thermoplastic resin and forming a molded elastomeric article by use of that thermoplastic resin. The inefficiency becomes even greater where a specially-formulated thermoplastic resin is procured for use in the molding process.
The crumb rubber material is not only available in great abundance, its constituents possess similar, if not identical, material compositions. For those reasons, crumb rubber material serves well as feedstock in forming a thermoplastic resin material. The inefficiencies in prior art approaches noted above are minimized, then, in accordance with the teachings of the present invention whereby crumb rubber or a like rubber composition is consumed as feedstock in a process wherein the necessary compounding of the feedstock into a thermoplastic resin material is accompanied by a substantially contemporaneous molding process that yields an article having a preselected contour and configuration.
2. Prior Art
Processes for molding a pre-processed rubber composition as feedstock in fabricating a molded elastomeric article are known in the art. Various pre-processing techniques for processing crumb rubber into a compounded form are also known in the art. The best prior art known to Applicant includes U.S. Pat. Nos. 5,114,648; 4,795,603; 4,244,841; 4,110,420; 4,028,288; 3,991,005; 3,386,925; 2,461,193; and, 2,409,437. This prior art, however, fails to disclose a method or system which receives as its feedstock unaltered crumb rubber and generates as its end product an elastomeric article molded essentially to its final contour and configuration.
For instance, U.S. Pat. No. 5,114,648 issued to Applicant is directed to a method of producing thermoplastic resin products. The disclosed method generates as its final product a pelletized resin compound, not an elastomeric article in its final configuration. While the method operates on a rubber-containing feedstock material, the method's end product is adapted for subsequent utilization in a separate molding process. There remains a prevailing need for a method and system wherein a recyclable material such as a scrap or waste rubber composition is consumed as feedstock, and wherein the pre-processing of the scrap or waste rubber composition and the fabrication of an elastomeric article resulting therefrom is contemporaneously performed in sufficiently efficient, inexpensive, and simple manner.